Hi! So I just got my tank and I decided to buy a red-blue halfmoon betta (I named him Avenue), and since he looks really small for his tank; I'm still in question whether to get him 4 pygmy cories and two amano shrimps as tank mates. My questions are:

-Is this overstocked, considering I have a 10 gallon tank? If so, should I reduce the number of pygmy cories?
-My betta is really active and he mastered his ways into coping with his tank (there's current created by the filter and an air pump), would this affect his relationship/compatibility with 4 pygmy cories?
-Do pygmy cories really need plants? Because all I have are artificial cabomba plants around the edges of the tank, (I decided I would go to artificial for the first few months.)

That is a fine set-up, I'd reccomend keeping 5-6 cories, since the pygmy cories are so tiny they prefer some more friends to make them feel safe. It is not overstocked, considering you have a 20 gallon filter.

Really a wildcard, you can't really know how they will react until you try it. I would reccomend you put the amanos in first, as if he won't tolerate them he definately won't tolerate the cories.

Live plants are completely optional. I have 3 tanks, one being a betta/nerite snail and two community tanks. One of the community tanks is a natural planted tank, meaning it has plants planted in soil, the other community tank has a bit of floating hornwort since it was growing too quickly for the other smaller community tank. The betta has no live plants, just silk, but I do plan on adding some of the hornwort since it grows so dang quickly. haha Only have live plants if you want the extra challenge, and your wallet can handle it. I'd reccomend some basic floating hornwort, as it is insanely hardy (actually an invasive species, impossible to kill), and about 3 dollars at petsmart for a small bundle which will quickly turn into a large bundle. Also, whenever you get live plants you will get some free pond snails along with it. These little guys don't poop much at all and stay tiny.

I really thought that the amount of fishes I plan to buy will overstock my tank, but turns out I could have more! I got excited after reading that I could keep 5-6 cories! And I'll try some hornwort (maybe just a bundle, will look really awkward with the ugly artificial plants I have, but oh well!), and if it goes well, hopefully I could reproduce that bundle so that I won't have to buy anymore. :) And I'm closer to a "Big Al's" so I don't think they have that exact same deal if I get a hornwort. But.. thanks again!

I just googled hornworts' care and I found out that it sheds crazy and could be a mess when it rots/dies. And someone recommended an Elodea, which should I get? Elodea or Hornworts? Which one is cheaper? And which one is better for a betta?

I read that too before I bought mine, but It hasn't shed that much at all, in what is has shed they are tiny and easily cleaned up. I could also reccomend water wisteria. Arounf the same price for a bundle, and in my experience has grown more quick than even the hornwort! You can plant this in the gravel or float it, it is much nicer looking than hornwort. Most plants from pet stores are between $3-$9 for a bundle. Most will be aroung $3-$6 though.

@MaisyDawgThirteen, changed my plans! There was no pygmies in any of my LFS! It's either they're popular or the LFS near me sucks! >.< So instead, I bought four white cloud minnow, which I know is very compatible with the betta! I've introduced them in the tank along with two amano shrimps. The first thirty minutes, my betta was basically chasing my minnows; but the dispute decreased and I haven't seen them fight/chase. Thanks for the advice though! I might buy a bigger tank and choose cories to live in it.

There is a big issue with WCMM, albeit peaceful and beautiful, they have much different temperature requirments to betta fish. Betta prefer 76-83F, while WCMM like 60-72F. They will live in higher temperatures but it can be detrimental to their health.